Cementum and dentin hypersensitivity is one of the most painful, ubiquitous, and least satisfactorally treated of chronic oral problems involving teeth. Painful reactions are commonly elicited by thermal, mechanical, and chemical stimuli which are transmitted to the pulp. To date, the precise mechanism for dentin sensitivity has not been established. However, hyperesthetic areas are easily identified; careful examination of these sites reveals that either the enamel or the cementum or both, have eroded or planed away leaving dentin exposed.
Home treatment is required as an adjunct to chairside therapy for hypersensitivity, as such therapy provides only temporary relief. Moreover, exposed root surfaces which are not kept clean may become increasingly hypersensitive. Because of the discomfort associated with brushing these areas, the patient tends to avoid them in his normal oral hygiene regimen. Without effective home care, any relief obtained in the dental office is likely to be transitory. Traditionally, home treatment has included a variety of medicaments which are intended to occlude or cover the lumina of the dentinal tubules.
A number of desensitizing formulations have been attempted with varying degrees of success and duration of effectiveness. One of the earlier dentifrices was a formalin-containing paste. Others have included zinc chloride, silver nitrate, glycerin, strontium chloride, and the fluorides, the latter two being of particular interest. The desensitizing effect of strontium chloride has been investigated for over a decade and is available commercially in a dentifrice. As early as 1943, the use of sodium fluoride for desensitizing dentin was reported. More recently, the effectiveness of stannous fluoride in an anhydrous glycerin gel has been demonstrated.